1. Field of the Invention
This invention relates to an electric ballast comprising an electric coil with coil windings having a width d which are wound on a synthetic resin coil base including a box-like base part comprising four faces arranged so as to form a rectangle for accommodating a metal core, said base part being provided on either side with mutually parallel flanges limiting the width d of the coil windings.
2. Description of the Related Art
An electric ballast of the type mentioned in the opening paragraph is known from EP-0 018 596. This known ballast can suitably be used, inter alia, as a ballast for an electric discharge lamp. In said known ballast, the coil base comprises lamellae which, after providing the coil windings, are turned over and secured with a free end to the base part so as to completely enclose the coil windings. The base part and the lamellae are made of an insulating synthetic resin and are manufactured in a single piece. Turning over the lamellae requires the presence of folding seams at the location where the lamellae meet the base part. This constitutes a drawback.